Electroscope picture reception



Dec, 30, 1924 1,521,192

l vc, F. JENKINS.-

ELEGTROSGOPE PI CTURE RECEPTION Filed Sept. ll, 1922 Patented Dec. 430, 1924.

UNITED STATES 1,521,192 PATENT OFFICE.

GHARILES FRANCIS JENKINS, OF WASHINGTON, DISTRICT 0F COLUMBIA, ASSIGNOR TOu RADIO PICTURES CORPORATION, OF WASHINGTON, DISTRICT OF COLUMBIA, A

CORPORATION.

ELECTROSCOPE PICTURE RECEPTION.

Application filed September 11, 1922. Serial No. 587,523.

To all ywhom t may concern.

Be it lrnownthat I, CHARLES FRANCIS JENKiNs, a citizen of the United States, residing at lVashington, District of Columbia, have invented certain new and useful Improvements in Electroscope Picture'Receptions, of which the following is a speciication.

This invention relates to the transmission of" pictures-by-radio, and has for its principal object means for interrupting a source of light at the receiving station, 1n order to produce lights and shades and half-tones on the photographic surface, upon which 1t impinges in the apparatus at the receiving station.

In the drawings herewith, Fig. l is a diagrammatic illustration yof the device, and Fig. Q. a detail thereof, in both of which A is the primary of an induction coil, andpart of the receiving apparatus; B the secondary of the same coil; C an amplifying tube, I) a battery in the plate circuit of the tube; E an induction coil, the primar of which is in circuit with the plate, andt e high tension secondary in circuit with the square plates F and F. Between the two plates, an extremely light iihn member G is hung, on the support H (Fig. 2). K is a source of light, 'M a lens for gathering the diverging rays thereof and concentrating them onto the target G attached to `the oscillatingmember Gr.H The lens N is so located that one focus thereof is on the target G", and the other focus is on a light-sensitive film R fed forward by the roller S.

The operation of the device 1s as follows: When fluctuating current represent-mg the light values of a picture is sent out from the' broadcasting station, it is picked up by the receiving station, and these iuctuating current values, passing through the low'side primary of the induction coil E, induces in the secondary of the transformer E a high potential of alternating character. The effect is to charge the plates F and F positive and negative, respectively, and alternately. The oscillating member Gr being grounded, as, for'example, on a water main, has but one sign, and, therefore, is attracted toward the plate which at the moment has the opi posite sign, and is repelled from the plate which has the same sign. As the two plates 'F and F constantly change their sign, it is obvious that the member G continually oscillates as it hangs between these two plates and in amplitude in proportion to the current energy.

JAnd as the light from the source K is directed onto the target G', when the latter is in neutral position the light-will be-cut off at that point; but as the member G, and its attached target G oscillates, the lightl will pass onto the lens N, and thence to the film R in greater or lesser amount,l as the oscillation of the member is great or small. The devices operate, therefore, as a lightinterrupting shutter which permits light to pass in proportion to the energy ofthe plate charging current.

What I claim, therefore is.-

1. In devices of the character described, a source of light, an electrostaticly charged oscillating member so located as to intercept light from said source, 'the oscillation of thelight intercepting member resulting from the member `being' electrically charge 2. In devices of the character described, a

source of light, two electro-staticly charged members 1n alignment with said light and an oscillating member so located therebetween as to intercept light from said source, said oscillating member suspended Eetween said electrostaticly charged memers.

3. In devices of the character described, the combination of a source of light and an oscillating member in line with said light, and propelled by an electrostaticly charged plate and so located as to vary the value of the light passing said oscillating member.

4. In devices of the class described, the

combination of a source of light, a pair of plates, means for potentially charging-same, and an oscillating member propelled by said plates potentially charged alternately plus and minus, and so located as to vary the value of the light passing said `oscillating member. Y

In testimony whereof I have affixed my signature.

CHARLES FRANCIS JENKINS. 

